Field of the Invention
The invention relates to an arrangement for providing vehicles with energy by magnetic induction. The arrangement comprises a primary side electric conductor arrangement or assembly adapted to generate an electromagnetic field while an alternating electric current flows through the conductor arrangement and a field shaping layer comprising magnetizable material adapted to shape magnetic field lines of the electromagnetic field.
Furthermore, the invention relates to a corresponding method of manufacturing the arrangement and to means adapted to shape magnetic field lines of an electromagnetic field which is produced by the electric conductor arrangement.
Description of Related Art
During operation of a system for providing vehicles with energy by magnetic induction, the electromagnetic field which is generated by the primary side electric conductor arrangement is received by a receiving device on the secondary side (the side of the vehicle) and the electromagnetic field energy is converted back into electric energy by magnetic induction. The invention especially relates to the primary side of such a system. The receiving device can be named “pick-up” and is part of the vehicle, while the primary side electric conductor arrangement is typically buried in the ground or is otherwise mechanically connected to the track of the vehicle or to the place where the vehicle may stop or may be parked.
The terms “primary side” and “secondary side” are used corresponding to the terminology which is used for transformers. In fact, the electric parts of a system for transferring electric energy from a vehicle track or from a vehicle stop to the vehicle by induction form a kind of transformer. The only difference compared to a conventional transformer is the fact that the vehicle, and thus the secondary side, can move.
WO 2010/000495 A1 describes a system and method for transferring electric energy to a vehicle. The energy can be transferred to the vehicle while the vehicle is moving. While the present invention may relate to such a system, it is not restricted to the transfer of energy to moving vehicles. Rather, the energy may be transferred while the vehicle temporarily stops (such as a bus at a bus stop) or while the vehicle is parked.
The vehicle may be any land vehicle, including track bound vehicles, such as conventional rail vehicles, mono-rail vehicles, trolley busses and vehicles which are guided on a track by other means. Other examples of land vehicles are road automobiles, including busses which are not track bound. For example, the vehicle may be a vehicle having an electrically operated propulsion motor. The vehicle may also be a vehicle having a hybrid propulsion system, e.g. a system which can be operated by electric energy or by other energy, such as electrochemically stored energy or fuel (e.g. natural gas, gasoline or petrol).
WO 2010/000495 A1 describes an example of serpentine windings on the primary side for producing the electromagnetic field. The primary side conductor assembly of the present invention, which is made of electrically conducting material that produces the electromagnetic field during operation while the electrically conducting material carries an alternating electric current, may have the same or a different configuration. In any case, at least sections and/or parts of the primary side conductor assembly has/have a length and a width, so that the primary side conductor assembly comprises lateral edges. For example, as described in WO 2010/000495 A1, sections of the primary side conductor assembly may extend along the track of the vehicle so that there are two lateral edges on opposite sides of the primary side conductor assembly. Other configurations are possible such as elongated electric conductors extending in the direction of travel, coils of electric conductors having several windings and arrangements of electric conductors having different configurations.
The features of a primary side conductor assembly which are described in the foregoing description may also apply to a secondary side conductor assembly, with the exception that this assembly is located on board the vehicle.
In any case, the primary side conductor assembly causes emissions of the electromagnetic field, which is produced by the primary side conductor assembly, to the surroundings. Corresponding limit values, in particular of the electromagnetic or magnetic field strength, must be observed. In addition, the secondary side conductor assembly also causes emissions.
The primary side conductor assembly and the secondary side conductor assembly should be coupled to each other in an effective manner.